SOLID STATE CHEMISTRY
The aim of the course is to provide the student with in-depth knowledge of the solid state and its symmetry properties, the general principles of diffraction as a direct consequence of the periodicity of atoms in the crystals, polymorphism, phase transitions and solids reactivity.
Specifically, the student will:
- Know the synthesis techniques of inorganic compounds and materials preparation, the reactivity of solids and the sintering process of ceramics. Know the main types of crystalline packing and the factors influencing them, the structural characterization techniques as well as understand the influence of crystalline symmetry on the properties of materials. Understand the principles of X-ray diffraction and its applications, as well as master the essential data analysis tools. Know the solid solutions and their importance in the materials science field.
- Identify, within the framework of the topics covered by the course, the appropriate approach to seek a specific goal through the use of appropriate synthesis or analysis techniques, demonstrating the ability to effectively apply the acquired knowledge.
- Be able to use the specific language and terminology of the discipline in order to communicate coherently what he/she learned.
The course deals with the fundamental topics of solid state chemistry, paying particular attention to the structure, properties and reactivity of matter in crystalline form. Wide space is devoted to the origin of the three-dimensional periodicity in crystalline structures, to the definition of symmetry and to its description through space groups. Students are introduced to the theoretical and practical aspects of X-ray diffraction and its applications, also through practical lessons involving real data analysis. The classification of crystal structures is discussed and the factors at their origin are described, as well as the characteristics of the most common crystallographic defects. Theoretical and practical aspects of solid state phase transitions, reactivity of solids and ceramics sintering process are introduced.
The crystal state. Origin of 3D-periodicity. Crystallization. Nucleation and growth. Amorphous materials and glasses.
Bravais lattice and crystal lattice. Symmetry classification. Point symmetry. Point groups of Bravais lattices: the 7 crystallographic systems. Point group of crystal lattices: the 32 crystallographic classes. Symmetry operation involving translation. Space groups of crystal lattices.
X-rays. Scattering process: Thompson and Compton. Atomic scattering factor. Scattering from ordered systems: the diffraction process. Bragg's law and Laue's equations. Reciprocal lattice. Ewald sphere. Structure factor and equation of the electron density. Reletionships between diffraction and lattice simmetry. The phase problem in crystallography and its possible solution.
Practical aspects of X-ray diffraction. Single crystal and powder diffraction. Crystallographic data bases.
Classification of crystal structures. Close packing and eutactic models. Principal types of binary and ternary structures.
Polymorphysmus and phase transitions. Kinetic and thermodynamic classifications. Continuos phase transitions. Crystallographic trends in phase transitions.
Solid solutions: interstitial and substitutional. Heterovalent substitutions and charge compensation mechanisms.
Reactivity of solid. Solid state reactions. Principles and mechanisms.Experimental aspects. Sintering and ceramic materials.
The notes of the lectures and all the supporting material are available to the students and shared on Elly portal. The software used for practical lessons is freeware and freely downloadable from the web for academic use. In addition to the shared material, the student can personally go further on some of the topics discussed during the course using the following books:
A.R. WEST Solid state chemistry and its application, John Wiley and Sons Ltd., Chichester
- C. Giacovazzo et al. Fundamentlas of Crystallography, Oxford Science Publications
- E. Moore and L. Smart Solid State Chemistry: An Introduction, CRC Press
The course counts 6 CFUs (one CFU, University Credits equals one ECTS credit and represents the workload of a student during educational activities aimed at passing the exams), which corresponds to 32 hours of lectures and 24 of practicals. The taught classes will be based mainly on lectures during which besides the projection of slides both educational and scientific freeware software will be employed. All the material will be uploaded on the Elly platform. Practical exercises will be carried out both in the classroom and in the laboratory, aimed at directly involving students in the learning process and demonstrating some practical applications of the topics covered, in particular through the refinement and interpretation of powder and single crystal diffraction data.
Verification of learning and acquired knowledge takes place by an oral exam, in which the student should demonstrate understanding and application ability of the fundamental concepts of the arguments treated in the lectures.